Abstract: In a flywheel assembled from a plurality of parts and having greatly reduced noise proportion for reciprocating-piston engines, especially hand-cranked diesel engines, a first part (17) comprises at least one steel plate, which is joined to at least one further part (22) by rivets, bolts, spot welds and/or fitting to achieve bearing contact therewith over an area, such that the parts are clamped against each other.

Abstract: An internal combustion engine has a sleeve in which the piston reciprocates during operation, as a result of which the sleeve is heated and tends to vibrate. The engine casing includes walls which define a space around the sleeve through which a liquid coolant is conveyed to cool the sleeve. A compressible member or medium is provided in such space or in the coolant therein and suppresses vibrations within the coolant, thereby minimizing the extent to which vibrations from the sleeve are transmitted through the coolant to the engine casing and produce noise in the region around the engine. In one preferred embodiment, the compressible medium is a plurality of gas bubbles distributed throughout the coolant. In another preferred embodiment, a compressible member is provided in the space adjacent the sleeve.